


Kingdom Hearts III: Dive to the Heart

by Mathemagician93



Category: Kingdom Hearts
Genre: Gen, Originally Posted on FanFiction.Net, final boss cutscenes, prediction based on what was available in 2014
Language: English
Status: Completed
Published: 2018-12-04
Updated: 2018-12-04
Packaged: 2019-09-06 16:08:17
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,030
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16836001
Author URL: https://archiveofourown.org/users/Mathemagician93/pseuds/Mathemagician93
Summary: The clash between the Thirteen Seekers of Darkness and the Seven Guardians of Light comes down to Sora fighting alone against Master Xehanort. But, when your heart is connected to so many people, are you ever truly alone? My imaginings of cutscenes that will play between the phases of the final fight against Xehanort.(Originally published October 2014. Spoilers through Dream Drop but nothing released afterwards)





	Kingdom Hearts III: Dive to the Heart

**Author's Note:**

> When I first started writing this in 2014, I was a bit naive and thought there was no way I would be able to write out an entire novelization of Kingdom Hearts III before it was published, especially since it had been announced at E3 2013. History proves I was wrong and could have at least written a good attempt at a full story, but I wanted to write down what I thought would make a good ending to the story. This covers only the cutscenes that would play between phases of the Xehanort fight, with the actual battle being set off by the OBJECTIVE prompt.

* * *

OBJECTIVE: Defeat Xehanort!

* * *

Sora collapsed to his knees, no longer having the strength to stand after the battle with Master Xehanort. The destined clash between the Seven Guardians of Light and the Thirteen Seekers of Darkness had finally come to pass, and Xehanort had succeeded in manifesting the X-Blade and unlocking Kingdom Hearts. Only Sora had managed to follow the deranged master into the heart of all the worlds, as the other six guardians and their allies were too busy with the other 12 incarnations of Xehanort and their army of Heartless and Nobodies. Leaving the wasteland of the Keyblade Graveyard behind, Sora had charged into what could only be described as a realm of swirling light and darkness, fighting against Xehanort at the very threshold of the old man's ideal world.

The ensuing battle had been extremely difficult, but Sora had barely managed to overcome Xehanort, even with the power of the legendary weapon. As the old man's body faded into darkness, Sora dismissed his Keyblade and turned his thoughts to his friends, who were facing almost twice as many Keyblade wielders in addition to a numerically superior army. He wished he could return to join them, but he didn't have the strength to summon his Keyblade again, let alone reopen the door to Kingdom Hearts and join the battle. It would be up to Riku, Kairi, Mickey, Aqua, Terra, and Ven to finish off the remaining 12 Seekers of Darkness, with the help of Axel, Goofy, Donald, and the Radiant Garden Restoration Committee. Sora's friends had always given him the power to save the world, and know he would have to place his trust in them. Sora felt a smile come to his face only to immediately disappear when he heard an all too familiar voice.

"So, this truly was the limit of your strength. It's a shame, really. You had so much potential as one of my vessels, yet you waste it. I would have thought after fighting both my Heartless and my Nobody you would have learned I cannot be defeated so easily."

Glancing towards the source of the voice, Sora saw Xehanort standing with a smirk on his face. If Sora had had more energy, he would have kicked himself- he should have known Xehanort wouldn't have faded into darkness now that he wasn't a Heartless or a Nobody. Apparently, he still had Xemnas's ability to create duplicates of himself, though this duplicate was stronger than Xemnas himself had been. Sora tried to re-summon his Keyblade, only to be rewarded with a flash of light and no weapon. Xehanort started to laugh at the display.

"I must admit, you were the only person that caused me to worry about succeeding. After all my years of study, I was certain I understood exactly how the heart worked, allowing me to access Kingdom Hearts itself. And then, you had to come along. I have never seen a Keyblade wielder like you. You managed restore Ventus's heart, give Vanitas a physical form, and maintain your own identity after becoming a Heartless. You have even managed to regain your full strength after having your heart shattered in the Sleeping Worlds and again after you removed my former apprentice's heart from your own. Seeing that, I was forced to come to only two conclusions: either my research was wrong, or your heart was much stronger than any I had seen before."

Unable to summon any real weapon, Sora was forced to respond with verbal combat. "You know, for someone who yelled at me for forgetting how our previous battles went, you should really listen to your own advice. I told Xemnas and Xigbar before- my friends are my power!"

Xehanort merely rolled his eyes. "Still sticking to that childish notion, are you? You may have impressed Braig with your proclamation, but borrowing power from others only opens you to further weaknesses. And even with their power, I have seen you are no match for me. Your heart is too scarred to be a real threat. But if you insist, I can eliminate that power before destroying you. My other selves are still fighting, and I can make sure they give your Princess of Heart and my Heartless's former vessel special attention…"

Xehanort could barely contain his smile as Sora let out a feral yell and became surrounded by a dark aura before he collapsed to the ground. For all his abilities, Sora had fallen for the exact same trap he had in the Sleeping Worlds and let too much darkness into his heart. If he hadn't already opened the door to Kingdom Hearts, this would have been the perfect time for Xehanort to turn Sora into another vessel, much like he had done with Terra years ago. Xehanort turned to walk away, but then turned back to Sora's unconscious form. He may not need Sora now that his plan was on the verge of success, but it couldn't hurt to have a backup. After all, his last attempt to forge the X-blade had been stopped. In the unlikely event that something could still stop him, it wouldn't hurt to hide a piece of his heart within a new vessel that none would suspect…

* * *

Sora expected to crash into the ground when he started falling forward, but when he fell for what seemed like a minute he opened his eyes to see himself apparently falling through an ocean. Recognizing the feeling, he wasn't too surprised when he saw his Station of Awakening appear below him. However, as soon as he could make out the details of the stained glass platform he let out a gasp. The entire platform was riddled with cracks, to the point where the pictures of Donald, Goofy, Riku, and Kairi were almost impossible to make out. Xehanort clearly hadn't been kidding when he said his heart was scarred.

Sora worried his heart wouldn't be able to withstand even a gentle landing, but before it could become an issue he was caught in a massive gust of wind. Trusting his own Dive to Heart to look out for his best interest, he started to use his Glide ability and followed the wind. He rode the air current until he saw another undamaged platform beneath him, where a standing figure with two Keyblades was waving at him. Seeing his Nobody, Sora realized what had happened. Roxas must have used Aeroga to create the air current, guiding him to a safe landing. As Sora descended to the platform, he started making out the design and couldn't help but smile. It was similar to most of his platforms, except featuring Roxas sleeping in the outfit he had worn during his time in Twilight Town. Instead of appearing to lean on the side of the station, the sleeping Roxas was facing straight ahead in the center of the station. To his left were circles with the faces of Hayner, Pence, and Olette over the image of the Oathkeeper Keyblade. On the reflected side of the platform over Oblivion were Axel and Naminé, as well as a third figure. At first, Sora thought it was Kairi, but then he noticed this girl had black hair. Sora almost immediately felt a profound sadness seeing her, but he couldn't remember who she was, even after getting most of Roxas's memories during his failed Mark of Mastery exam.

Sora was snapped out of his musings when his feet touched down gently on the platform, accompanied by Roxas walking up to him with a smile. "You okay, Sora? I wasn't sure how well I could adjust Aeroga to catch you, but I figured anything would be better than letting you go crashing into your damaged platform." Sora put his hands behind his head as he grinned. "Yeah, I'm fine thanks to you. The spell worked great, and I love what you've done to this platform. How did you even do that, anyway?"

Roxas dismissed his Keyblades as he shrugged. "I'm not too sure I did anything about it. I really tried just fading away and fully joining with you, but it wasn't working so well. I even immersed myself in your memories, and got as far as piecing together the pieces that were broken apart from Castle Oblivion. I thought delving into your heart would help me disappear, but I ended up falling onto this platform instead. Call me crazy, but seeing Hayner's crew, Axel, and Naminé made me rethink trying to disappear."

"Why would I call you crazy for thinking that? You've always had just as much right to exist as I do, and it sounds like your friends helped convince you of that. If there's anything this whole experience has taught me, it's that you can always count on your friends to help pull you out of the darkness. Besides, this platform might be why you had such a hard time disappearing. From the looks of things, I'd say this is your heart, not mine. It's even got all of your friends, though I'm not sure who that black-haired girl is. I know you already gave me most of your memories and it sounds like you've gone through most of mine, but I don't know who she is."

"Whoa, slow down there Sora. I don't think this platform proves I have a heart. Besides, last time I did a Dive to the Heart it was into your heart a few days before I joined with you. This platform might be mine, but I'd say it's just a part of our heart now instead of me having my own individual heart. More like you and I are two parts of the same whole instead of being two completely different people sharing the same body."

Sora laughed. "I guess I can live with that. It's much better than the whole 'we're the exact same person' stuff you've been saying ever since we beat Xemnas…" Sora trailed off as he remembered the present situation. "Well, beat Xemnas the first time. I guess he's still technically around now that Xehanort's back. Should we really be standing here while he's about to take over Kingdom Hearts? It's nice talking with you, but there's probably a better time for it than right now."

Roxas let out a sigh. "Well, we should be worried about what Xehanort can do, but not as much as you think. Time doesn't really have any meaning while we're just talking here like this, since this is all inside our own heart. Sure, you disappeared from the real world when I pulled you here to fight, but that's because I pulled you into a Dark Corridor before the fight started since I wasn't sure if it was possible for us to be interrupted. Still, it took me a while to pull you in, seeing as you did pass out. Xehanort will probably have had a few seconds to act when we get you back to the outside world."

"I'm not quite sure I entirely get it, but a few seconds is better than the alternative. At least we don't have to hurry back- it's kind of nice not being in constant pain from the fight. Since we've got so much time to talk, though, you never answered my question. Who's the girl in this picture? I'm pretty sure Kairi never dyed her hair black, and whoever this girl is she was obviously important to you seeing as she's right next to Axel, who I know is your best friend."

Roxas let out a small chuckle. "I bet Axel loves the fact that you still call him that. He can try convincing everyone his name is Lea now, but to me he'll always be Axel. I guess that rubbed off on you too. If he complains, just tell him it's Roxas's fault and he'll have to get it memorized." Roxas grinned at his joke, but it was quickly replaced by a frown as he turned to look down at the unknown picture. "As for who she is, I wish I could tell you. I know she was important to me from how much sadness I feel when I see her, but I can't remember who she is. She must be tied to the reason I turned on the Organization, though. I don't remember why I did that either, but that memory gives me the same feeling of hurt and loss as her face does. I might not know the reason, but I was certain turning against the Organization was something I had to do, and it's similar with her. I don't know who she was or why she was important to me, but I just know she was." Roxas shook his head and turned back to Sora. "I'm not making much sense, am I?"

"I think I understand it. It sounds like what Kairi said about the year she couldn't remember me- knowing someone is missing, but not knowing who they were. Maybe something similar happened to her? You could always try asking Naminé when this is all over. She'd probably be the person to go to for any questions involving memories. Plus, it would be nice—"

Sora was interrupted when Roxas's platform started to shake and darken, as if the light flowing through the glass was being cut off. Roxas immediately summoned Oathkeeper and Oblivion, and his outfit changed instantly from his Twilight Town clothes into his Organization XIII cloak. Sora guessed this was just an effect of him getting ready to battle, as apart from a short fight with Axel Roxas hadn't really used any of his power while living in the digital Twilight Town. Considering he was currently part of a massive battle against 13 copies of the same person coming from all different points in time, Sora wasn't that quick to question how something as simple as a change in clothes was possible.

Just when the light was about to fade entirely from the platform, Roxas created thirteen pillars of light that spread outward and dissipated the darkness. The light pillars remained around the outside edge of the station, revealing the source of the darkness: another copy of Xehanort. Sora could quickly guess what had happened: when he passed out, Xehanort must have implanted a fragment of his heart. That had been his plan all along in the Sleeping Worlds, and he must have taken advantage of Sora's temporary defeat to try it again. Still, Sora wasn't about to give up. So what if he had a part of Xehanort's heart inside of him? Riku had managed to fight off Ansem for over a year, and he had been born from the entirety of Xehanort's heart. If Riku could do that alone, there was no way Sora wouldn't be able to beat this fragment with Roxas's help.

Holding out his hand, Sora tried summoning his Keyblade once again, though it didn't appear instantaneously. Focusing harder, he managed to get the usual flash of light to appear, though it coincided with the sound of cracking glass in the distance and a sudden bout of chest pain. Roxas never took his eyes off of the Xehanort fragment, but he directed his words to Sora. "Listen, don't keep trying to summon your Keyblade. It doesn't sound like your part of the heart can handle the strain, and I got this. This guy was the real leader of Organization XIII, and I never got a chance to officially hand in my resignation!"

* * *

OBJECTIVE: Take control of Roxas and defeat the Xehanort fragment!

* * *

Watching Roxas fight the Xehanort fragment, Sora began to wonder how he had managed to beat his Nobody in their fight. This version of Xehanort seemed to rely more on magic than physical attacks, throwing orbs of darkness at Roxas as his main form of attack. However, Roxas's light powers easily cut through the attacks, allowing the Key of Destiny to lay waste to his former boss. Sora could tell Roxas was basically showing off, repeatedly using his Light Dash ability to get hits in before Xehanort could even react. However, after taking a fair bit of damage, the Xehanort fragment summoned Ansem's old guardian. Sora was about to warn Roxas about this creature, but Roxas seemed to enjoy the new challenge.

"I'm glad you managed to summon that thing, Xehanort. Last time I saw that, Riku used it to get a surprise attack in and beat me. I never got a chance to test me strength against it. Let's see how your dark guardian withstands the full force of my light. Magic Hour!"

As he shouted this, Roxas unleashed the full force of his Limit Break. Holding both his Keyblades aloft, he called down a barrage of giant pillars of light that blasted the guardian to pieces. Not even the Xehanort fragment withstood the attack, leaving no traces of a battle behind but some swirling tendrils of darkness. Roxas let his Keyblades fade away as he turned to Sora with a sheepish grin. "I think I might have overdid it a bit at the end there. I forgot how draining using a Limit Break could be. I'm going to need a second to catch my breath."

Sora laughed. "Sure, take all the time you need, you showoff—look out!" Quickly pulling Roxas down to the ground, Sora managed to evade the wave of darkness that suddenly shot at head height throughout the platform. Getting back up, he saw the source of the blast was a pulsating ball of darkness that must have coalesced from the remnants of Xehanort and his guardian. The orb of darkness suddenly expanded into the familiar form of a Darkside. Staring at the giant Heartless while unable to summon his Keyblade, Sora gulped.

"So, Roxas, got enough energy left to take out—" Before Sora could finish his sentence, the Darkside was bombarded with orbs of orange light, stunning the creature. Sora could only stare in disbelief. "Nice job with the Ragnarok, Roxas. Though if you could pull that off, why did you need the break?" Roxas shook his head. "Don't look at me. The only time I've seen Ragnarok was in your memories. But if I didn't do it, you can't do it at the moment, and Ven is already out of here, who just saved us?"

As if in response to Roxas's question, a figure wearing an Organization XIII cloak crashed into the platform. It was far from a graceful landing, and while the figure started to stand up Sora noticed the Keyblade they were wielding- it had the same shape as the Kingdom Key, but the blade was black, the handle was purple, and the guard was silver. However, before he could give any more attention to the weapon, the figure had gotten back to their feet and started taking their hood down.

As soon as Roxas and Sora saw the figure's face, they let out a gasp. It was the same girl from the picture on the station! She dusted off her cloak and smiled at Roxas and Sora. "Sorry I'm late, guys, but in order to get this new Keyblade I had to go through this really tedious tutorial session. Like I'd ever forget how to use a Keyblade, but you know how Dives to the Heart can be. Oops, sorry, be back in a second."

She then charged her Keyblade with light energy and unleashed a furious series of blows on the recovered Darkside. Sora recognized the pattern as his own Ars Arcanum attack, but she followed the combination with Roxas's Event Horizon to send pillars of light travelling outward from herself through the Darkside. As the giant Heartless was finally destroyed, the girl went back to Sora and Roxas, who could only stare dumbfounded at her. "What's wrong, guys?"

"Who… are you?" The girl let out a sigh at Roxas and Sora's unison response. "I thought seeing me might trigger Roxas's memories, but I guess not. To make a long story short, my name is Xion. I was a Replica of Roxas made by Vexen that absorbed Sora's memories from Castle Oblivion to make my own identity. I was the fourteenth member of Organization XIII, and a backup plan in case Roxas failed to collect enough hearts. I was the reason it took so long for Sora to wake up, since Naminé couldn't restore the memories trapped inside me. When the Organization decided they didn't need both me and Roxas, I let him kill me so Sora's memories could return. Since I was a memory being, when I died and returned to Sora all memories of me disappeared too. At least, that's my understanding. You'd have to ask Naminé if you want a better chance of getting real answers."

Roxas seemed to be struck dumb at the revelation that he had killed someone important to him and forgotten all about it, but Sora was handling this slightly better. "Well, Xion, I'm not really sure if I can believe your story, but thanks for helping us. We'll just have to talk with Naminé after we beat Xehanort for good."

* * *

Xehanort walked deeper into the realm within Kingdom Hearts, searching for a way to make use of its unlimited power. However, when a voice behind him called out his name, he turned to see Sora back on his feet. Judging from the hatred in his tone, he had somehow overcome the attempted possession.

"So, you must have defeated the fragment of my heart, Sora. It's too bad I have to hold back so much, but splitting my heart 14 ways must have been a bit beyond me. Still, you have troubled me one too many times. I'm done holding back!"

Xehanort charged at Sora with the X-blade, only to find his blow stopped by the combination of Oathkeeper and Oblivion. Immediately recognizing the situation, Xehanort started laughing. "So, it isn't Sora, but Roxas who confronts me. Did you take advantage of my fight with Sora in order to retake control of that body? Perhaps I discarded you too quickly in the past. I see now that you and I have a lot in common."

Roxas struggled to keep Xehanort's weapon at bay, but he rose to Xehanort's taunt. "I'm nothing like you. Sora asked me to take the lead in this fight. It isn't a matter of one taking control away from the other. We've always shared a body, but now we share the same heart. He's not just a vessel, he's my other!"

"An inspiring speech, but misguided. You may delude yourself into believing you are better than I am because you are willing to share, but that is only a sign of weakness. Do not worry, such weakness will not remain once I have created the ideal universe."

With this, Xehanort put even more force into his attack, driving Roxas back. Even the combined strength of Oathkeeper and Oblivion wasn't a match for the legendary power of the X-blade. Just as Roxas was about to fall, however, a third Keyblade materialized above his head and struck out at Xehanort, knocking the old man back. Roxas recognized Xion's Keyblade, but wasn't sure what caused it to appear. Quickly going back into his shared heart, he found Xion sitting on the ground with her eyes closed in intense focus. "Thanks for another save, Xion. How did you even manage to do that?"

"Can't… talk… need… to…focus…" was the only response he got from Xion, so Roxas turned to Sora, who just shrugged. "I guess she just made it work? From the looks of things, though, you need all the help you can get. If she can get her Keyblade to materialize out in the real world, then I can too. You both gave up your existences for my sake, so if I end up losing myself trying to help you I'll just be returning the favor. Now, let's stop this thing once and for all!"

* * *

OBTAINED: Ultima Form

Sora, Roxas, and Xion all combine their power. Use the Drive Command to change into Ultima Form and unleash the power of four Keyblades!

* * *

OBJECTIVE: Defeat Master Xehanort!


End file.
